Thermal barrier coatings provide a means of thermal insulation of gas turbine components exposed to elevated temperatures. They undergo severe microstructural changes and material degradation, which have been implemented in this work by means of a sequentially coupled microstructural mechanical calculation that made use of a self-consistent constitutive model within finite element calculations. Analyses for different temperatures and bond coat compositions were run, which reproduced the trends reported in previous research and identified the accumulation of high out-of-plane tensile stresses within the alumina layer as an additional phenomenon that could drive high temperature crack nucleation.

Description:

This is the author’s version of a work that was accepted for publication in Materials Science and Engineering: A . Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Materials Science and Engineering: A vol 513-514, pp. 302-310, 2009, DOI: 10.1016/j.msea.2009.02.006

Sponsor:

The authors gratefully acknowledge the support of the Engineering and Physical Sciences Research Council (EPSRC) via the SuperGen 2 Plant Lifetime
Extension project [grant no. GR/586334/01].